1. Field of the Invention
The present invention relates generally to automated storage libraries for storing and retrieving computer data, and more particularly to systems and methods for arranging and housing media drive assemblies in automated storage libraries.
2. Description of the Related Art
A popular device for the handling and storage of large amounts of information in a data processing system includes an automated storage library system. Automated storage library systems generally decrease the access speed and increase reliability of data storage libraries containing large amounts of information. Automated storage library systems typically include a plurality of storage media devices, a transport mechanism, and one or more storage media drives in communication with a computer system for inputting and outputting desired information to and from the plurality of media devices.
Storage media devices such as cartridges housing magnetic tape with data stored thereon have proven to be an efficient and effective medium for data storage in computer systems, including automated storage libraries. Automated storage libraries including tape cartridges generally have a plurality of storage bins or slots for storing tape cartridges, a robotic retrieval/transport mechanism (often referred to as a “picker”), and one or more tape drives. The robotic picker may be controlled to select a specific storage tape cartridge from the library and transfer the tape cartridge between a storage slot and a tape drive within seconds. The robotic picker typically includes a gripper or hand mechanism positioned on the robotic picker to controllably retrieve and transport a tape cartridge within the storage library.
An automated storage cartridge library is typically interfaced to a computer system such as a computer network or the like. The storage library or interfaced computer system may index the location of the tape cartridges and their associated stored data within the storage library for later retrieval of the stored information. When desired, the storage library may be activated to retrieve a desired storage tape and load it into a drive to access the stored information and/or write new information. In large storage libraries multiple tape drives are generally employed to increase access and storage performance by operating in parallel as well as providing back-up drives in case of failure, maintenance, and the like.
Generally, the number of media drives included within an automated library system is tailored to the end user's desired capacity for data storage and/or access time. Automated storage libraries are often manufactured, however, with the infrastructure or hardware, including power supplies, cabling, interface communication electronics, etc. to support a full complement or maximum number of tape drives within the library housing. For example, the library may include the electrical power and interface electronics to support up to 12 tape drives even though a significant number of users might desire less than the full complement of tape drives, for example, only four tape drives.
Storage libraries are generally manufactured with the hardware and infrastructure to support the maximum number of tape drives to reduce overall manufacturing costs despite the varying number of possible tape drives that may be included in a storage library system. Additionally, future field upgrades of the storage library to include additional drives is made easier with the hardware and infrastructures already included in the system. This practice, however, raises the overall cost and complexity of the library system for those users who use or desire less than the maximum number of tape drives because the unused infrastructure and hardware to support additional drives is not fully realized.
Alternatively, each storage library system may be custom manufactured with the infrastructure and hardware to fit varying numbers of media drives. Custom manufacturing, however, increases the average cost and time of manufacturing storage library systems. Additionally, field upgrades of a storage library system may be more difficult and costly because additional infrastructure, hardware, and testing may be necessary for the system to support additional drives.
Therefore, what is needed is an automated storage library system and method for incrementally including a number of tape drives efficiently within a storage library system housing. For example, reducing the amount of unused infrastructure within the library system when less than the maximum number of drives are used is desired. It is also desired that additional drives may be added to the storage library system in the field efficiently and with sufficient power, cabling, interface communication electronics, etc. to support the additional drives.